This invention relates to devices for forming cylinders of a predetermined length and diameter, and in one aspect to devices for forming such cylinders from a heat shrinkable material and applying the cylinders in an unshrunk condition about objects such as the butted ends of two items or the closed ends of containers such as capped or corked bottle necks; which cylinders may subsequently be shrunk about the objects to form seals.
Heretofore many such seals applied around objects (such as the ends of capped or corked bottles containing alcoholic beverages) have consisted of seamless tubular lengths of heat shrinkable material. In a typical application, such a seamless tube of unshrunk heat shrinkable material is positioned around an object, and then heat shrunk to the contour of the object to provide a satisfactory, but expensive seal.
Heat shrinkable tapes have been used to provide a less expensive seal for certain types of objects by wrapping a length of the tape around each of the objects and subsequently applying heat to conform the tape thereto (see U.S. Pat. No. 3,873,018). The ends of the tape forming the axial seams in such seals must be smoothly overlapped and pressed firmly together prior to shrinking, however, for if they are not the seams will part and curl during the heat shrinking process, leaving unsightly or otherwise unsatisfactory seals. Thus heretofore tape could only be used around portions of objects having generally cylindrical surfaces which provided proper support for forming the seams and tape could not be reliably used to form seals around portions of objects having very irregular surfaces.